Design, make and test a Sundial.

Extracts from this document...

Introduction

Sundial Coursework

Statement of Task:

To design, make and test a Sundial.

Introduction:

The sundial is the oldest know device for measuring time. The first confirmed uses of it where by the Babylonians in around 2000BC. However it is safe to say that shadows have been used as a rough measure of time ever since primitive man discovered that as the day progresses the shadows of trees and rocks get shorter and then longer again.

The sundials used by the Babylonians were hollow half spheres, set with edges flat and with a small bead at the centre. As the day wore on the shadow of the bead followed a circular arc, which is divided into 12 “temporary hours” (they changed through the seasons).

A modern sundial consists of a plane (dial face) and the gnomon (style). The dial face is divided into hours and the gnomon is the flat piece of metal, or stick in the dials centre, it points towards the North Pole (in the northern hemisphere) or South Pole (in the southern hemisphere).

I will make the base of my Sundial out of MDF wood as it a cheap and a relatively durable material, it is also very easy to work with, plus it will be made weatherproof with varnishing. I will use steel sheeting for my style, as it is thin, strong and easy to cut into the required shape. My sundial will be about 20cm x 20cm big. I will need to have a template for the markings on the sundial, such as the one shown below.

This template was made using the following instructions exerted from my GCSE Astronomy text book: “Divide a square into two by the line AB. Select a point, C for the position of the style. Draw the line DCE, at right angles to AB, which will be our 6 o’clock line. Draw CG, making angle ACG equal to your latitude 51°.

Therefore the time when the sundial reads 11 is (11:00)-(+0:02) or 10:58, but I then have to add the hour difference between the two time zones to obtain an exact sundial time of 11:58.

The testing took place on a Latitude of about 1°30’W. We must times this by 4 to achieve a correction of 6 minutes, which must be added to the sundial time.

This means we achieve a final Sundial time of 12:04.

Evaluation:

Overall I think that the project was a success. My Sundial, whilst not very impressive in appearance, worked successfully. I successfully used the equation of time to achieve an accurate time from my sundial. My sundial would work well all year round, however you would need to add an hour in the summer as well as using the equation of time. If I was to do the project again I think I would spend more time on the Sundial itself, varnishing it and making sure it was completed with more time to spare so I could do further tests. Overall I am pleased with how the project has gone, and I have found it to be relatively successful.

Related AS and A Level Core & Pure Mathematics essays

the increase for the second number is 12. Therefore I know that the next formula is C =12H-40 Again I use the Substitution method that I used to find the connect 5 formula. This produced two parts of equations. (4W-12)H-(12W-32), which I simplified to 4Wh-12H-12W+32. This is the formula for finding the number of connects in any size box when you are connecting 5.

128 - 15 5. = 113 Successful The formula I found seems to be successful as I have shown on the previous page. I will now use the formula to find the number of squares in a higher sequence. So now I wil use the formula 2n<sup>2</sup> - 2n + 1 to try and find the number of squares contained in sequence 20.